Managing Ecological Risks of Contaminated Sediment

Much effort has gone into determining the extent of contamination of sediments. However, inadequate attention has been devoted to the implications of classifying a sediment as contaminated. Because sediments are usually addressed under water-oriented regulations, the typical response is to remove contaminated sediments from the waterway. This may or may not be appropriate. In water, most sediments are anoxic, reduced, and near neutral in pH; the resource at risk is the aquatic community. If a sediment is removed from the water, it will dry over time, oxidize, and often decline in pH; the resources at risk include ground water, air, and terrestrial communities. Inadequate consideration of physicochemical conditions and resources at risk associated with various management options can lead to relocating and exacerbating, rather than solving, contaminated sediment problems. Attention must not focus on “might this sediment be a problem in the waterway?” but rather “if this sediment warrants special attention, what is the most appropriate environmental management option?”